Data sharing and storage platform Box can be profitable within five years and would reject a Microsoft takeover offer if one were made, Dylan Smith, co-founder and chief financial officer of Box, told CNBC.

"Right now, we're very much focused on growth but we're very mindful of being a profitable company someday as well and we expect to get there in a few years," Smith said. "There's no specific timeline but certainly in less than five years."

"The decision to go public is largely a function of our vision for the company, and our choice and belief that we can create a lot more value by building a very large independent public company and less a function of demand."

He said that even if Microsoft offered $1.5 billion for Box, he and co-founder Aaron Levie would reject the offer. "We would definitely not take that offer from Microsoft - we are putting that on record."

The cloud-based data sharing company was created from the dormitory room of co-founder Aaron Levie in 2005. Now, the company has more than 15 million users. The company had a valuation of $1.2 billion in July last year, based on a funding round, which raised $125 million, The Wall Street Journal reported.

Smith denied the data storage solutions market was too crowded, saying companies like Box were building "fundamentally better products." He also defended the firm's timetable for turning profitable.

"Because we're going after such a massive opportunity – a $40 billion market – when we look at the opportunity and the overall model we look at the potential to build that market-leading company and the economics, the customer expansion and retention and a lot of different things."

"Our investors certainly have expectations around our profitability as well so it's an ongoing conversation," he added.